Crimen et Delictum, V (April 2013) International Journal of Criminological and Investigative Sciences 14 Neurobiology of aggressive behaviour: focus on psychopathy. Stefano Barlati 1 , Patrizia Trapella 2 , Luca Massaro 3 Abstract (english version) Violent behaviour appears to be the result of a complex net of interacting genetic as well as environmental factors. Both antisocial personality disorder (ASPD) and psychopathy are associated with a propensity towards violence, although there is some evidence that psychopathy may be associated with instrumental aggression, while ASPD is more associated with reactive aggression. People with psychopathic personality are characterized by a constellation of traits including interpersonal affective features (e.g. lack of affect and emotion) and antisocial features (e.g. impulsive and aggressive behaviour). Cognitive and affective emotional processing deficits associated with brain abnormalities, particularly structural and functional impairments in the orbitofrontal prefrontal cortex and amygdale, have been found in psychopathy. Frontal and temporal 1 Clinical and Forensic Psychiatrist. Criminologist. Member of the Scientific Committee of the Advanced High School of Criminological Sciences – CRINVE, FDE Institute of Mantua. Member of the Scientific Committee of LIBRA Association. | Psichiatra, psicoterapeuta. Esperto in Scienze Criminologiche e Investigative. Membro del Coordinamento Scientifico della Scuola di Alta Formazione in Scienze Criminologiche – CRINVE. Membro del Comitato Scientifico dell’Associazione LIBRA – Rete per lo Studio e lo Sviluppo delle Dinamiche di Mediazione. 2 Criminal Lawyer and Expert in Criminology. | Avvocato Penalista, Esperto in Scienze Criminologiche. 3 Forensic Medical, Master in Criminology and Forensic Psychiatry and Expert in Criminology. | Medico Legale, Master in Criminologia e Psichiatria forense, Esperto in Scienze Criminologiche. lobe abnormalities are associated with violent behaviour, such that prefrontal deficits have been associated with behavioural disinhibition, increased risk taking, and impulsivity, whereas the temporal lobes, among others, are involved in affect regulation and sexual behaviour. Psychopathy has not traditionally been associated with generalized cognitive or intellectual dysfunctions, but rather with circumscribed deficits in specific neuropsychological domains. Based on research using neuropsychological assessments and other techniques, several cognitive characteristics appear to exist among subjects with psychopathy, such as cognitive inflexibility, attention deficits and inappropriate processing of contextual cues in the environment. The neuroscience of psychopathy is a field undergoing rapid growth and, like any field in its nascent stages, is vulnerable to methodological inconsistencies and subsequent interpretive variations. Although psychopathy is a major area of research in psychology and criminology, much remains unknown about its etiological underpinnings. Heterogeneity of the genetic and the neurocognitive findings may be partly due to the existence of different subtypes of psychopaths. Future studies need to examine the relationships between genes and interpersonal, behavioural and neuropsychological features of psychopathy, in addition and in combination with their role in legal decision-making. Keywords: Aggressive Behaviour, Psychopathy, Genetics, Neurocognitive Functions, Neuropsychology.